# HG changeset patch
# User KUDr <KUDr@openttd.org>
# Date 1172263870 0
# Node ID a8303346cd9cf0b24ab6c710bd778e3d340ae306
# Parent  31f85e2d51008f7fda21d9461f2a6e9634852797
(svn r8864) -Codechange: make ClrBitT(), SetBitT() and ToggleBitT more like CLRBIT() and so on (modify value of the first parameter instead or returning the result)

diff --git a/src/helpers.hpp b/src/helpers.hpp
--- a/src/helpers.hpp
+++ b/src/helpers.hpp
@@ -138,25 +138,19 @@
 	}
 };
 
-template <typename T> FORCEINLINE T ClrBitT(T t, int bit_index)
+template <typename T> void ClrBitT(T &t, int bit_index)
 {
-	int val = t;
-	CLRBIT(val, bit_index);
-	return (T)val;
+	t = (T)(t & ~((T)1 << bit_index));
 }
 
-template <typename T> FORCEINLINE T SetBitT(T t, int bit_index)
+template <typename T> void SetBitT(T &t, int bit_index)
 {
-	int val = t;
-	SETBIT(val, bit_index);
-	return (T)val;
+	t = (T)(t | ((T)1 << bit_index));
 }
 
-template <typename T> FORCEINLINE T ToggleBitT(T t, int bit_index)
+template <typename T> void ToggleBitT(T &t, int bit_index)
 {
-	int val = t;
-	TOGGLEBIT(val, bit_index);
-	return (T)val;
+	t = (T)(t ^ ((T)1 << bit_index));
 }
 
 #endif /* HELPERS_HPP */
diff --git a/src/rail.h b/src/rail.h
--- a/src/rail.h
+++ b/src/rail.h
@@ -261,7 +261,7 @@
 {
 	if (*tracks != TRACK_BIT_NONE && *tracks != INVALID_TRACK_BIT) {
 		Track first = (Track)FIND_FIRST_BIT(*tracks);
-		*tracks = ClrBitT(*tracks, first);
+		ClrBitT(*tracks, first);
 		return first;
 	}
 	return INVALID_TRACK;
@@ -274,7 +274,7 @@
 {
 	if (*trackdirs != TRACKDIR_BIT_NONE && *trackdirs != INVALID_TRACKDIR_BIT) {
 		Trackdir first = (Trackdir)FindFirstBit2x64(*trackdirs);
-		*trackdirs = ClrBitT(*trackdirs, first);
+		ClrBitT(*trackdirs, first);
 		return first;
 	}
 	return INVALID_TRACKDIR;
diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -450,7 +450,7 @@
 		(trdy >= 0 && dy < 0)
 	) {
 		if (!HASBIT(*trackdir, 3)) { // first direction is invalid, try the other
-			*trackdir = SetBitT(*trackdir, 3); // reverse the direction
+			SetBitT(*trackdir, 3); // reverse the direction
 			trdx = -trdx;
 			trdy = -trdy;
 		} else { // other direction is invalid too, invalid drag
@@ -513,7 +513,7 @@
 		tile += ToTileIndexDiff(_trackdelta[trackdir]);
 
 		// toggle railbit for the non-diagonal tracks
-		if (!IsDiagonalTrackdir(trackdir)) trackdir = ToggleBitT(trackdir, 0);
+		if (!IsDiagonalTrackdir(trackdir)) ToggleBitT(trackdir, 0);
 	}
 
 	return (total_cost == 0) ? CMD_ERROR : total_cost;
@@ -777,7 +777,7 @@
 		signal_ctr++;
 
 		// toggle railbit for the non-diagonal tracks (|, -- tracks)
-		if (!IsDiagonalTrackdir(trackdir)) trackdir = ToggleBitT(trackdir, 0);
+		if (!IsDiagonalTrackdir(trackdir)) ToggleBitT(trackdir, 0);
 	}
 
 	return error ? CMD_ERROR : total_cost;
diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp
--- a/src/town_cmd.cpp
+++ b/src/town_cmd.cpp
@@ -730,7 +730,7 @@
 
 		// Exclude the source position from the bitmask
 		// and return if no more road blocks available
-		mask = ClrBitT(mask, (block ^ 2));
+		ClrBitT(mask, (block ^ 2));
 		if (mask == 0)
 			return _grow_town_result;